Which hematoxylin is most preferred for IHC stains?

• A. Mayer Hematoxylin
• B. Harris Hematoxylin
• C. Ehrlich's hematoxylin
• D. Weigert's hematoxylin

Answer: (A)

For IHC stains, the counterstain should reveal nuclear detail clearly without obscuring or interfering with the chromogen signal. Mayer's hematoxylin is preferred because it is water-soluble and formulation-stable, producing crisp blue nuclei with minimal background. This balance helps the chromogen signal (often brown DAB) stand out clearly.

Other hematoxylins tend to be more variable or harsher in IHC contexts. Harris and Ehrlich's hematoxylin can yield stronger or more background staining and are more sensitive to preparation differences. Weigert's hematoxylin, being an iron-hematoxylin, is typically used for elastic fiber or specific staining and can be too intense or require careful differentiation, which is less ideal for routine IHC counterstaining.